OBJECTIVETo develop a sensitive and specific microarray for detecting mutations of HBV pre-core/core and basic core promoter regions in the clinic.

METHODSSite-specific oligonucleotide probes were designed and immobilized to microarray slides and hybridized to HBV gene fragments amplified with specific biotin-labeled primer using asymmetrical PCR. The specificity and sensitivity of the method were estimated. And the microarray was applied to detect 138 clinical serum samples with HBV-DNA.

RESULTSThe mutations of HBV pre-core/core and basic core promoter regions can be specifically detected using the microarray, and the sensitivity was 1 x 10(1) copies/microl. Among 138 samples, 40 samples had T1762/ A1764 mutation, 11 samples had C1814 mutation, and 16 samples had A1896 mutation. The A1896 mutation rate in high HBV-DNA load group was significantly higher than that in low HBV-DNA load group (P < 0.01).

CONCLUSIONAn DNA microarray assay was successfully established to detect the mutations in HBV pre-core/core and basic core promoter regions. The A1896 mutation in pre-core/core region maybe involve in duplication of HBV.